Computer input devices, such as a mouse, a tracking ball, and a touch pad, are not only designed to work with application software and to monitor the X-Y plane movement, but also provide "click" function to allow a user to do on-screen display selection. However, such an input device has to be pointed to the scrolling bar of the screen display in order to scroll the screen. Thus, the screen cursor has to be repeatedly positioned between the working area on the screen and the scrolling bar. Apparently, it is inconvenient to computer users. Further, in selecting files or application software which is not currently shown in the monitor screen, the user has to hide the present file first and then uses the push-buttons or keys of the input device to sequentially change the sub-directory with repeated "double click" action. Such a process is quite boring and tedious.
Thus in order to simplify and enhance the operation, computer input devices with another dimension of input function (referred as Z-axis control) are developed, for example the Taiwan patent application No. 84208070 filed in the name of the present inventor which, cooperating with software, allows a computer user to scroll the screen or to select desired application software no matter where the screen cursor is located.
Although computer input devices with Z-axis control are already available in the market, yet it is still desirable to provide a novel design of a computer input device with Z-axis control to meet various styles of computer users in operating the input devices. FIG. 1 shows a conventional multi-dimension computer mouse 80, wherein the Z-axis control is achieved by depressing two resilient pads provided under the middle key 81 of the computer mouse with the index finger or the middle finger and, in this case, the thumb may be used to perform control of different functions. Alternatively, the Z-axis control may be arranged on one side of the mouse to be operated by the thumb in case that the middle key of the mouse is arranged for other functions.
Further, a computer mouse is usually provided with two or three keys and, besides these keys, there is no other push-button available in the mouse. Obviously, it limits the development and exploitation of the application software under current computer environment. Thus, the present inventor has developed a computer mouse devised with a side switching device which is disclosed in Taiwan patent application No. 85201274. The present inventive computer mouse described herein may also be added with the side switching device, if needed, to further enhance the control provided by the computer mouse.